Preheat oven to 350°F (177°C). Line a large baking sheet with parchment paper or a silicone baking mat.
Add oat flour and baking powder into a medium mixing bowl. Whisk until evenly combined. See notes for how to properly measure the oat flour.
Add mashed bananas to a separate large mixing bowl. Add in the oat flour mixture, reserving 1/4 cup. Use a spatula to mix the bananas and the oat mixture until oat flour is fully incorporated. Your dough should be very sticky. Add in a little of the remaining flour, 1 tbsp at a time, mixing until just incorporated, until the dough is dry enough that you are able to break off a piece of dough and shape it into a ball without the dough completely sticking to your hands. You don't want to overmix because the dough will become too sticky again.
Divide dough into 9 pieces. Roll one piece between your palms to form a smooth ball. Place onto prepared baking mat. Repeat with remaining dough pieces, spacing bread rolls 2 inches apart. I recommend washing your hands in between each ball to prevent the dough from sticking to your hands. If desired, you can add a few quick or rolled oats on top of each bread roll before baking.
Bake bread rolls for about 18-20 minutes or until bread rolls look cooked and tops are lightly golden brown. If you are unsure if the bread is cooked, you can cut one open to test.
Notes
I added a few quick oats on top of each dough ball before they baked for appearance. It's completely optional.
When measuring the oat flour, do not directly scoop measuring cup into the flour. Instead, spoon the flour into the measuring cup and then level off the top with a knife. This will prevent you from overpacking the flour which would result in dense and dry rolls.
Make sure that your mashed bananas are not too liquidy. They should be mashed but with some small chunks. See photo in post for reference. If your bananas are too liquidy, your dough will be too sticky and you will need to add more oat flour which will make your rolls dry and dense.
The rolls are very lightly sweetened with bananas. If you prefer sweeter rolls you can sprinkle some sugar on top before baking or add some sugar to the dough.
These rolls are best eaten the day of. If you have leftovers, I recommend storing them in an airtight container in the fridge and heating them up before eating.
If you don't have oat flour you can make your own by processing rolled oats in a food processor or high powered blender until it becomes the consistency of flour.
The nutrition information provided are only estimates based on an online nutritional calculator. This is not a comprehensive list of all the nutrients in the recipe (i.e., does not include vitamins, cholesterol, etc). I am not a certified nutritionist. Please consult a nutritionist or doctor for accurate information and any dietary restrictions and concerns you may have.